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Abstract:

A multiple zone HVAC system comprises powered flow rate adjustable
registers. It can further comprise zone controllers that can wirelessly
control the registers, and a central controller that controls the HVAC
unit and coordinates zone controllers.

Claims:

1. A multiple zone climate control system, comprisinga. a HVAC unit that
supplies conditioned air to more than one zone; wherein the HVAC unit
contains a heating unit or a cooling unit or combination thereof.b. a
zone controller in the zone requiring climate control;c. a central
controller, said central controller controls said HVAC unit to be in a
state selected from heating, cooling, ventilating, and off; wherein the
central controller turns off the heating or cooling unit after all zones
or selected zones reach their preset conditions respectively and turns on
the heating or cooling unit after a predefined number of zone's preset
condition is not met.d. one or more air flow rate regulating devices in
each zone requiring climate control, wherein each said air flow rate
regulating devices is powered and is built into a register or placed on
top of the register, each said air flow rate regulating device comprises
one or more dampers or boosters or combination thereof and an air flow
rate regulating device controller, wherein said air flow rate regulating
device controller can communicate with said zone controller or central
controller and adjust the degree of openness of said damper accordingly
or adjust the performance of said booster accordingly to reach a desired
climate control which is set at the zone controller in each zone; ande. a
digital wireless network that connects said central controller, said zone
controllers and said air flow rate regulating devices, wherein said zone
controllers communicate with the central controller through said digital
wireless network.

2. The multiple zone climate system in claim 1, wherein said zone
controllers communicate with the central controller and the air flow rate
regulating devices.

3. The multiple zone climate control system in claim 1, wherein the
central fan in said HVAC unit is adjustable to compensate the closeness
of said dampers.

4. The multiple zone climate control system in claim 3, wherein the speed
of said central fan increases when more said dampers are closed.

5. The multiple zone climate control system in claim 4, wherein the speed
of said central fan is controlled by the central controller.

6. The multiple zone climate control system in claim 1, wherein the
capacity of said heating unit or cooling unit is adjustable according the
volume of airflow passing through.

7. The multiple zone climate control system in claim 6, wherein said
heating unit produce less heating when less air pass though it or said
cooling unit produce less cooling when less air pass through it.

8. The multiple zone climate control system in claim 7, wherein the
performance of said heating unit or cooling unit is controlled by the
central controller.

9. The multiple zone climate control system in claim 1, wherein said air
flow rate regulating device controller is controlled by said zone
controller.

10. The multiple zone climate control system in claim 1, wherein said air
flow rate regulating device controller is controlled by said central
controller.

11. A climate control system, comprisinga. a HVAC unit that supplies
conditioned air to more than one zone; wherein the HVAC unit contains a
heating unit or a cooling unit or combination thereof.b. one or more air
flow rate regulating devices in each zone requiring climate control,
wherein each said air flow rate regulating devices is powered booster fan
and is built into a register or placed on top of the register, wherein
the on/off of said fan is controlled by a pair of temperature sensor
resistors.

12. The climate control system in claim 11, wherein said air flow rate
regulating devices further comprise an air purification component.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001]This is a Continuation-In-Part application of U.S. application Ser.
No. 10/702,241, filed Nov. 6, 2003, the disclosures of which are
incorporated herein by reference in their entirety. It also claims
priority to U.S. Provisional Application No. 61/278,890, filed on Oct.
14, 2009, which provisional application is hereby incorporated by
reference in its entirety. The entire disclosure of the prior application
is considered to be part of the disclosure of the instant application and
is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002]1.Field of the Invention

[0003]This invention relates to a duct type air conditioning system (AC
system), which is capable of energy efficiently regulating temperature in
each room (or zone) independently as well as providing other air
conditioning functions such as ventilation, humidifying, cleaning and
filtering air in each room independently.

[0004]2.Background Information

[0005]In most residential houses, one or more central HVACs (heating,
ventilation and air-conditioning) are used to send conditioned air to
designated rooms. Usually, one thermostat controls the temperature of
several rooms or zones. Due to differences in ventilation efficiency and
exterior thermal load among different zones, not all zones can achieve
the temperature set at the single thermostat control. It is common that
rooms on the upper floor have much higher temperature in the summer than
rooms in lower floor. In winter, rooms in northwest corner or above the
garage of a house usually have lower temperatures than other rooms. With
a single thermostat, occupants in different zones cannot select their own
comfort level. Moreover, for a zone where the thermostat is not located
to reach a certain level, all other zones have to rise or fall at the
same time. This is a great waste of energy. Therefore, it is highly
desirable that the temperature and possibly other air comfort and quality
measures in each zone can be controlled individually.

[0006]These solutions, however, are usually complex and expensive and thus
hard to justify from cost saving point of view. For example, the
solutions by Parker et al. (U.S. Pat. Nos. 4,530,395, 4,646,964,
4,931,948) require dampers fitted inside ducts, thus incurring high
installation and maintenance costs. Ho et al. (U.S. Pat. No. 5,833,134)
use dampers in registers to control airflows, but the design calls for
the register dampers to be manually controlled, thus barring the
possibility of automatic zone temperature control. Hampton et al. (U.S.
Pat. No. 5,271,558) require turbines be placed in the register and the
turbines be connected to power generators. Their invention does not have
coordination among zone thermostats either. The current invention
presents a simple and inexpensive individual-zone controlled HVAC system.

SUMMARY OF THE INVENTION

[0007]The duct type forced air central HVAC system normally contains the
ducts connecting each room to deliver conditioned air, a thermostat and a
HVAC unit. The HVAC unit normally contains a heating/cooling unit and a
central fan or fans that blow air through the heating/cooling unit to
produce cooled/heated air. The HVAC unit normally contains an in house
part and an outside part for heat exchange.

[0008]One aspect of the current invention provides a system capable of
regulating temperature (and/or humidity, air quality, etc.) in each zone
independently, which can be incorporated into a new AC system as well as
be added on to an existing AC system with low cost and easy installation.
The system comprises a HVAC unit that supplies conditioned air; a central
controller (central control unit) that controls the HVAC unit and
coordinates with the control unit in each zone; zone controller (zone
control unit) in every zone requiring air conditioning to control the
zone air flow rate regulating devices, which could be dampers, air
blowers (boosters) or the combination of dampers and boosters, and send
zone data to central controller; air flow rate regulating devices such as
battery powered dampers on registers (with and without an air blower that
may require additional power) and/or air blowers in each zone requiring
air conditioning to regulate the flow rate of conditioned air; and use of
intelligent digital wireless communication network (e.g. using IR or RF
signal) to connect all components of the system listed above. This system
avoids the need of extensive wiring and large-scale modification on the
existing ductwork of a building to realize independent zone climate
control. The air purification unit can also be integrated with the
airflow rate regulating devices. It is preferred that the zone controller
and the zone register be installed in majority of or all the rooms. A
zone can be one room or multiple rooms based on the user's need.

[0009]Central control unit has multiple functions. It controls the HVAC
unit and optionally coordinates the zone control units; it may also
function as a zone controller that controls the airflow rate regulating
devices in the zone where the central controller is located. After the
zones have reached the preset conditions, the central controller changes
the status of the HVAC unit such as stopping the HVAC unit from cooling
or heating. However, it is not always necessary to have a central
controller to have zone controller functionality and a separate zone
controller can be used to control the zone where the central controller
is located.

[0010]The central control unit controls whether the system is in a
heating, cooling or ventilation state or off state. It can either turn on
the cooling/heating of the HVAC unit or stop the HVAC unit from
cooling/heating or optionally adjust the cooling/heating performance to
produce more or less cooling/heating. The room (zone) controller detects
the state (e.g. room temperature) in the corresponding room and act
accordingly. For example, considering a situation where a room control
unit sets the room temperature to be 70° F. and the actual room
temperature is 65° F.; if the central control unit sets the state
of the HVAC unit as cooling therefore the HVAC unit is producing cool air
and delivering it to the duct, the room control unit will send command to
the air regulating device to close the dampers and/or stop the boosters,
so the cooling air from the duct will not enter the room or enter less;
if the actual room temperature is 75° F., the room control unit
will open the dampers and/or start the boosters, so the cooling air from
the duct will enter the room or enter more to reduce the temperature in
that room until 70° F. is reached.

[0011]On the other hand, assuming the central control unit set the HVAC
unit in the heating state; if a room control unit sets the room
temperature to be 70° F. and the actual room temperature is
65° F., the room control unit will open the dampers and/or start
the boosters to allow the hot air coming in or allow more air coming in;
if the actual room temperature is 75° F., the room control unit
will close the dampers and/or stop the boosters, so the hot air from the
duct will not enter the room or enter less. When the central controller
sets the system state to be ventilation, all dampers will usually be kept
in an open status.

[0012]A mode selection switch or the like can be added to the central
control unit. For example, the mode could be either heating or cooling or
off; therefore in summer, the mode of the central control unit is set to
cooling and in winter the mode of the central control unit is set to
heating.

[0013]In one example, when the mode is set by the user to be cooling
(summer), if the temperature setting in one or more zone is not reached
because one or more zone is too hot, the zone controller in this
zone/zones will inform the central controller their temperature setting
and their room temperature (or simply inform the central controller that
this zone's setting is not reached); the central control unit will keep
the HVAC unit at active cooling state producing cool air to the duct; the
damper in these zones is open and/or the booster fan in these zones is on
to allow the cooling air entering these zones; when one of the zone is
cool enough therefore reach the temperature setting, the zone controller
will send out wireless signal to the register to close the damper and/or
turn off the booster; it will also send wireless signal to the central
controller to report the setting is meet. When the central controller
receives setting meet signal from all the zones or predefined zones, it
will stop the HVAC unit from producing cool air. After a period of time,
the temperature in these zones will rise again. Once a zone controller
detect its zone temperature not meet the setting, it will send signal to
the registers in this zone to open the damper/start the booster fan. It
will also send data of its current temperature/set temperature or a
setting not meet signal to the central controller; therefore the central
controller will restart the HVAC unit to produce cool air.

[0014]In one embodiment the zone controller control the airflow rate
regulating device directly by its own decision (e.g. opening the damper
based on the difference between the setting temperature and the real
temperature in the zone controller). In another embodiment the zone
controller control does not make decision to the airflow rate regulating
device for its status, the central controller make the decision and send
the decision to the zone controller and then the zone controller send the
corresponding command to the airflow rate regulating device to set its
status. In the third embodiment, both the zone controller and central
controllers can make the decision and the central controller can override
the decision of the zone controller if there is a conflict.

[0015]In some embodiments, an energy saving mode can also be used, which
is in the process of HVAC to cool or heat multi zones, when only a small
number of (e.g. one or two) zones do not meet the setting temperature and
the rest zones meet the settings, the central controller can turn off the
heating/cooling unit and only keep the central fan on, therefore the air
from zones that meet the temperature setting will be blown to the zones
not meet the setting to cool or heat these zones. This algorithm can be
used in the case that the temperature settings from different zones are
same or close. For existing residential housing use, this can be a common
case.

[0016]In another embodiment of energy saving mode, if the zone controller
in the zone of the air intake of the HVAC unit senses that the
temperature meet the setting while most other zones do not or the
temperature in the zone of the air intake is cooler than most other zones
in the summer or warmer than other zones in winter, the central
controller will turn on the central fan but not the heating/cooling unit
therefore these better conditioned air will go to other zones to
heat/cool them. For example, many homes have a HVAC installed in the
basement and the air intake is also in the basement, in the summer, the
basement normally is much cooler than other floors therefore the central
fan only can be turned on to utilize the cold air in the basement to cool
the other floors.

[0017]Similarly if the mode is heating in the winter, each satisfied zone
will closes its damper/stops its booster; if all the zones are satisfied,
the central controller will turn off the heating of the HVAC unit. Once
the temperature drops again, the unsatisfied zone controller will open
the damper/start the booster in this zone and inform the central
controller; the central controller will then turn on the heating of the
HVAC unit.

[0018]In the above example, what turn on the HVAC is one unsatisfied zone
controller and what turn off the HVAC is all zone need to be satisfied.
Different algorithms/logics used by the central controller can also be
adopted instead. For example, two unsatisfied zones is required to turn
on the HVAC system and 60% zones satisfied or several important zones
satisfied will turn off the HVAC unit. More algorithms are described in
the later part of the current invention.

[0019]In some embodiments, the zone controller will keep the damper
open/booster on for an additional period of time even after its setting
is met. The central controller can also keep the cooling/heating on for
an additional period of time even after all the setting is met; or keep
the cooling/heating off for an additional period of time even after the
setting not met is detected.

[0020]The control units contain microprocessors and can be programmed to
deliver sophisticated and concerted functions. For example, the degree of
openness of a damper and the speed of the fans in the boosters can be
programmed as a function of the speed of temperature change and the
difference between the set and actual temperatures in the zone, in order
for zones to reach the set temperature simultaneously. Battery can be
used to supply power to the central and zone control units. Wireless
power source can also be used to power them or used in combination with
battery (preferably rechargeable battery).

[0021]The status of air flow rate regulating devices (e.g. damper and/or
booster) is controlled by the zone control units or the central control
unit or both of them to regulate flow rate of conditioned air into each
zone. In the simplest case, the damper can just assume two statuses, open
and closed; the booster can also have only two states: on and off, if a
booster is incorporated into the system. In a more sophisticated case, a
damper can assume any status between being complete open and complete
closed, and an algorithm in the zone control unit or the central control
unit can be programmed to make the degree of openness of a damper to be a
function of temperature difference between the actual and set temperature
of the zone; the status/performance of the boosters can also be adjusted
accordingly. In the most sophisticated case, the central control unit and
zone control units work together to control the status of dampers and the
status/performance of the boosters in all zones in order to achieve the
set conditions in every zone in the most efficient manner. As the control
units are programmable, the control algorithm can be set at installation
and changed when needed later.

[0022]Programming to the central controller can be done manually by the
key pad or touch screen on the central controller, or by connecting it to
a personal computer through an USB port or the like, in another case,
when the computer is connected on internet, the central controller can
also be programmed through the internet connection remotely.

[0023]As there are usually multiple zones in a building, it is important
there is no communication interference between control unit in one zone
and airflow rate regulating devices in another. There are many well known
methods to address this issue. Various means are available to pair zone
control units and their corresponding air flow rate regulating devices
(e.g. powered wireless registers). For example, every component can be
assigned a unique network address in the wireless network composed of the
HVAC unit, the central controller, zone controller and air flow rate
regulating devices. A standard network communication protocol can be used
to carry messages between the network components without possibility of
interference/miscommunication. For example, one means is to pair a zone
controller and its zone air flow rate regulating device by registering
the air flow rate regulating device to the zone controller through an
initial "talk" at time of installation.

[0024]In some embodiments, the powered dampers in this invention are built
into a register, which is the piece that covers the exit of a duct into a
zone. Registers can easily be removed and exchanged without having to
tear open the ducts. This feature in combination with the wireless
communication feature makes the invention easy to install and maintain. A
communication unit on this air flow rate regulating device receives
instructions from its zone controller and sends commands to a mechanism
that controls the status of the damper utilizing motor or other suitable
electro-magnetic device. In some embodiments, communication unit on the
air flow rate regulating device receives wireless instructions directly
from the central control unit or both the central controller and the zone
controller.

[0025]The boosters in this invention can also be built into a register,
which is the piece that covers the exit of a duct into a zone. Fans are
added to the registers. The boosters utilize the fan to boost the airflow
rate. This feature in combination with the wireless communication feature
makes the invention easy to install and maintain. The registers equipped
with boosters can also have dampers on their covers or underneath the
fan. A communication unit on the register with booster receives
instruction from its zone controller and sends commands to a mechanism
that controls the status of the booster (e.g. on/off or speed of the
fan). In some cases, it receives instructions directly from the central
controller or both the zone controller and central controller. In some
embodiments, battery power may not be sufficient for booster. An external
AC or DC power source can be used. Wireless power source can also be used
to power them or used in combination with battery (preferably
rechargeable battery). The zone air flow rate regulating devices and/or
zone controllers and/or central control unit can use wireless power
system as their power supply such as Nikola Tesla's long-range wireless
energy; directional energy transfer such as lasers; induction-based
energy transfer systems, and those described in www.witricity.com and
etc. The combination of battery and wireless power can also be used. For
example, they use rechargeable battery to provide power and when the
battery is running low, a remote wireless power supply will charge the
battery through a wireless power receiver in the register or control unit
(e.g. they will send out a battery low wireless signal to start the
wireless power supply for charging).

[0026]Battery only can be used to supply power to all electrical
components on a damper. Low power consumption circuits and components
make it possible for the batteries to last a long time. Moreover, battery
level detection function can be built in. The damper battery level can be
checked regularly. Many well known methods can be used to check the
battery level. If battery level is deemed lower, a signal or sign can be
displayed on the zone controller or on the register with damper. An
external AC or DC power source can also be used instead of battery.
Wireless power source can also be used to power them or used in
combination with battery (preferably rechargeable battery) as previously
described.

[0027]There can be a manual override for the airflow regulating device
status on the zone controller or the airflow regulating device. When the
manual override is engaged, the zone controller set the
airflow-regulating device in a certain status until the override mode is
revoked.

[0028]If the air purification unit is integrated with the register with
booster or damper, they can be made to synchronize with the
booster/damper. For example, if the damper is open and/or the booster is
on, the air purification unit is turned on automatically; if the damper
is close and/or the booster is off, the air purification unit is turned
off automatically too.

[0029]In some embodiments, instead built into the registers, the airflow
rate regulating device is damper or booster fan or combination that can
be placed in the duct directly connecting to the target zone or the
damper or booster fan or combination built in the duct directly
connecting to the target zone.

[0030]Closing dampers/registers will usually reduce total airflow volume.
Too little airflow may have adverse effect on some type of HVAC unit,
such as icing or overheating. A temperature sensor can be placed inside
the heating/cooling unit or inside or on the duct wall near the heat
exchange component of the central HVAC unit. The sensor can send measured
temperature to the central control unit. If freezing or over heating
situation is detected, the central control unit could change the heating
or cooling operation into ventilation operation or stop the
heating/cooling. The sensor can also be connected directly with the
heating/cooling unit to control it on/off directly without going through
the central controller to do so. Another method to avoid too small
airflow volume passing through the heating/cooling unit is to have a
bypass in the duct. The bypass will be open to release some air before
the air going to the ducts to each rooms if too low airflow is detected
or to be resulted therefore although the air going to each room are
decreased the air passing the heating/cooling unit will not decrease too
much. The open/close of the bypass can be controlled by the temperature
sensor or the central controller or simply by a pressure sensor since too
low airflow will increase the pressure inside the duct. An example of the
bypass is a pressure release valve installed in the duct after the
heating/cooling unit. To save energy, the released air can be directed to
the major air inlet of the heating/cooling unit.

[0031]Too low airflow volume may also result in unacceptable airflow
pressure in some type of HVAC unit and the ducts. To ensure the airflow
volume is acceptable, a number of means (e.g. algorithms in the central
controller) can be employed, including keeping certain registers always
open, using booster fans, allowing a certain amount of airflow through
the register even when a register is closed, setting zone dead band
according to degree of temperature fluctuation in the zone, using a
pressure sensor in the HVAC unit or the bypass ducts to prevent too low
airflow volume etc. One example is to set a minimal number of the dampers
that need to be always open. Another example is allowing the damper to
cover only partial duct even in fully closed position. A third example is
to allow three status of the damper: fully open, partially open and fully
closed (damper fully covers the exit of the duct in its fully close
status); algorithms can be applied to dynamically control these dampers
to keep certain flow rate while having maximal independent climate
control and energy saving effects.

[0032]In some embodiments, the performance (power) of the fan in the
central HVAC system is adjustable. This fan (central fan) in the central
HVAC system blow the air through the heating/cooling unit therefore
produces and sends cooled/heated air to the duct connecting to each room.
When more damper in the registers are closed, the fan will speed up to
increase the air flow speed in those not closed registers therefore keep
the total airflow in the HVAC system constant or not decrease too much,
when more damper in the registers are open, it will slow down to decrease
the air flow in those opened registers therefore keep the total airflow
in the HVAC system constant or not vary too much. The speed of the motor
of the fan can be made adjustable to adjust the power (performance) of
the fan. In some cases, the performance of fan is controlled by the
central controller. The central controller can have a wire connected to
the fan control to send the command or the communication between them can
be wireless, in which case the fan control needs to be coupled with a
wireless receiver. The fan can also be controlled by the temperature. If
overheat or overcooling of the heating/cooling unit is detected by the
temperature sensor in the HVAC unit (e.g. the icing/overheating sensor
previously described), the fan will speed up to below enough air passing
through the heating/cooling unit to change their temperature to normal.

[0033]In some other embodiments, the performance of the heating/cooling
unit of the central HVAC system is adjustable. For example it can utilize
a variable frequency AC to produce different cooling capacity in the
summer. When more dampers in the registers are closed, it will provide
less cooling; when more dampers in the registers are open, it will
provide more cooling. Therefore the over cooling will not happen. In some
cases, the performance of heating/cooling unit is controlled by the
central controller. In the winter, when more registers are closed, less
gas is provided for burning in the heater of the HVAC if gas is used for
heating; or uses less electricity such as using less heating elements or
lower voltage if electricity is used for heating in the HVAC. In many
variable frequency AC systems, the speed of the motor of the condenser is
adjustable therefore the amount of cooling and heating (heat pump) it
produced is adjustable. In some embodiments, the speed adjustment is
controlled by the central controller. In some other embodiments, it is
controlled by the temperature sensor similar to the central fan control
mechanism.

[0034]The combination of using adjustable fan and adjustable
heating/cooling unit can also be used to accommodate the changed airflow
volume. The power of the heating/cooling unit will be decreased if the
airflow volume passing through heating/cooling unit is decreased
therefore avoid the over heating/cooling.

[0035]Examples of the invention described above are further illustrated in
FIG. 1˜12.

[0036]For many homes, it is safe to use dampers in the register as the
only airflow rate regulating device in the system. However, some homes
have ducts poorly constructed, which have too low flow rate even in
normal operating condition (single zone). Using dampers only in these
homes to achieve multi-zoning may result in unacceptable low flow rate
and therefore may cause problems to the central HVAC unit. For these
homes, the boosters described above or the combination of boosters and
dampers above is can be used as the preferred airflow rate regulating
devices. One aspect of the current invention relates to a register type
booster system for the duct type air conditioning system, which is
capable of regulating airflow rate in each room (or zones) automatically.
In some-embodiments, the booster system utilizes the previously described
central control unit and zone controllers. In other embodiments, the
previously described central control unit and zone controllers are not
used.

[0037]The method utilizes powered booster system equipped with fan in each
room to control the flow rate of conditioned air therefore increase the
air flow to this room to control the temperature in the room. Although in
some cases the previously described central control unit and zone
controllers are not used, a central booster controller can be used, which
only control the booster and does not control the HVAC unit. The central
booster controller can also use wireless (such as radio signals)
communication between it and the boosters to control the on/off or speed
of the fan in the booster (FIG. 13, 14).

[0038]The booster could either be a detachable device that can be placed
in front of the exit of the register or directly built into the register.
One example of the detachable device is a box shape frame that can cover
the exit of the register; the fan/fans and control part are inside the
box similar to the device described in U.S. Pat. No. 4,809,593. In some
embodiments, the booster is preferably built into a register, which is
the piece that covers the exit of a duct into a zone/room. Registers can
easily be removed and exchanged without having to tear open the ducts.
The advantage of built in register type booster is that it gives less
noise, higher air boosting efficacy and better outside looking.

[0039]There are many ways to control the operations of the boosters. It
can be turned on/off manfully or be to synchronize with the on/off of the
existing HVAC system. In one format, it utilize a central control unit
and zone controller described above, in another format, a central booster
controller senses the on/off of the HVAC device, and then sends out
wireless signal to control the on/off or speed of the fan of the
boosters. In the third format, each booster has its own sensor (e.g. a
temperature sensor or air flow rate sensor) that can sensor the on/off of
the HVAC system to turn the fan on or off or adjust the speed of the fan
without the need of the central booster controller.

[0040]One way is to have a thermostat capable of detecting the room
temperature and duct air temperature to regulate the booster. The booster
is turned on and off based on whether the HVAC unit is on as well as the
relationship between the duct air temperature, the room temperature and
the set temperature. For example, if the room temperature meets the set
temperature, the booster will be turned off. In another example, assuming
that the booster thermostat is set to be 70° F., the room
temperature is 80° F., and currently the booster is off; if the
HVAC unit is turned on and the air temperature inside the duct is below
80° F., the booster (the fan or fans) will be turned on; the
booster will remains off if the duct air temperature is equal to or above
80° F. even when the HVAC unit is turned on. The booster
thermostat can be placed either on the booster or in a separately
location controlling the booster remotely. In another example, the
booster can be set either in heating or cooling state. When it is in
cooling state, if it senses cool air coming from the duct (air
temperature in the duct lower than the room temperature), it will turn on
the booster. If no cool air coming, it will turn off. When it is in
heating state, if it sensor hot air coming from the duct (air temperature
in the duct higher than the room temperature), it will turn on the
booster; otherwise it turn off the booster.

[0041]If central booster controller is utilized, there are several methods
for the sensor of the central booster controller to sense the on/off of
the HVAC unit. These methods can be used independently or in combination
with each other. One example is that the sensor device could be a small
unit attached on the heating/cooling/ventilation part of the HVAC unite
or nearby. It senses the vibration or noise caused by the running of the
HVAC unit to determine if the HVAC is on or off. It then sends out
wireless signal to turn on or off the boosters in all the zones/rooms
accordingly. Another example is that it could be a device attached to an
open duct of the HVAC system or be placed inside the duct. Once it senses
the air flow from the duct, it starts the remote boosters via wireless
communication. In the third example, the sensor device is connected to
the existed thermostat via wires. It therefore is able to detect the
control signal of the thermostat for the HVAC unit, and thus controls the
boosters based on the signal from the thermostat. If the thermostat sends
a signal to the HVAC unit to turn it on, the sensor will pick up this
signal and the central booster controller will send out signal to start
the booster. In the fourth example, the sensor detect the difference
between the room temperature and air temperature from the HVAC device and
therefore to control the booster. The booster can also be turn on and off
based on the relationship between the air temperature from the HVAC
device, the room temperature and the set temperature. In one example,
when the booster is off, if the sensor in the booster or the central
booster controller senses the temperature change in the duct, the booster
will be turned on, when the temperature change again, it will be turned
off. When using temperature difference described above or airflow in the
duct to control the booster's on/off, one can also equip each booster
with its own independent temperature sensors/air flow sensor to control
its own on/off, therefore in this case, central booster controller and
wireless communication may not be needed.

[0042]Varieties of controls can also be incorporated into the booster
system. Such as fan speed control and temperature control to make people
feel more comfortable. The control unit could be either placed on the
booster or placed separately to control the booster remotely.

[0043]Battery can be used as the power of the central booster controller
for easy installation. Preferably the booster employs safe low voltage
power. For example, a voltage or power adapter/transformer can be
employed to transform/convert dangerous high voltage AC power to the
needed safe low voltage DC power. An example of a booster system contains
the register frame, the motor driven fan(s) built into the register, the
power source and if needed, the sensor or wireless communication unit
receiving instructions from the central booster controller or the central
control unit. The wireless communication unit could be built either
inside the register or outside the register such as integrated with the
power adapter. The booster and/or central booster controller can use
wireless power system as their power supply such as Nikola Tesla's
long-range wireless energy; directional energy transfer such as lasers;
induction-based energy transfer systems, and those described in
www.witricity.com and etc. The combination of battery and wireless power
can also be used. For example, they use rechargeable battery to provide
power and when the battery is running low, a remote wireless power supply
will charge the battery through a wireless power receiver in the register
or control unit (e.g. they will send out a battery low wireless signal to
start the wireless power supply for charging).

[0044]When central booster controller is used, one example of using this
method is illustrated below in details: A system (FIG. 13) is to be
installed in an existing home to enable a single zoned AC system
regulating airflow rate in different room. The central booster controller
comprises a power line or battery powered sensor, which use a vibration
(or sound) sensor such as a microphone to pick up the noise of the
running of the cooling/heating/ventilation unit of the HVAC system. Once
the HVAC system is running, the central booster controller sends out
wireless signal to all the remote booster system (FIG. 14) in the
installed rooms. The wireless communication unit in the booster system
receives the signal and turn on the fan of the booster. Once the HVAC
stops, the central booster controller senses the absence of the noise and
sends out wireless signals to shut down the fan(s) of the booster system.

[0045]However, the easiest way is to use the powered boosters without any
sensors or central booster controller. The booster is turned on or off
manually by the user. Without any user operation, it is always on or off.
This feature is especially useful for the upper level rooms in the summer
since it sucks up the cold air from the ducts. A fan speed control can
also be added to the booster to adjust the flow rate (e.g., by adjusting
the voltage output of the voltage or power adapter/transformer if it is
employed).

[0046]Alternatively, a sensor (e.g. a temperature sensor or airflow
sensor) can be connected to or built within each booster directly to
control it's on/off without the need of wireless communication. If
airflow sensor is used, in order to distinguish the airflow caused by the
HVAC system and the booster itself, the following strategy can be used:
the fan of the booster will automatically shut off every small time
interval (e.g. one minute), if the air flow rate sensor the air flow even
when the fan is off, it will start the fan. An example of the airflow
rate sensor, which is placed inside the register, is described in FIGS.
15a and 15b and FIGS. 16a and 16b.

[0047]As shown on FIGS. 15a and 15b, a pair of temperature sensor
resistors (R1 and R2) with resistance 100 Ω at 25° C. and
400 Ω at 80° C. , and a pair of regular resistors, (R3 and
R4) with resistance 10 Ω, are used. A bridge circuitry is consisted
of these 4 resistors. In the structure of the vent register and sensor,
R1 is placed in a no air flow chamber and R2 is placed on the vent wind
channel, as shown FIG. 15b. With a 12 V voltage applied on the bridge,
output voltages Vn and Vw are measured by a microprocessor. When with AC
is off, the 12V voltage will heat the R1 and R2 to about 80° C.
The resistance will be about 400 Ω. The output voltage Vn and Vw
would be very close. When the main central fan of AC is on, with the
airflow cooling the R2, the temperature of the resistor would decrease to
about 40° C. in summer and 30° C. in winter, so that it
will reduce the resistance of R2 significantly. The output voltage of Vw
will be increased. Algorithms will be embedded on a microprocessor to
determine the AC on/off by measuring the change of Vw by reference of Vn,
such as if the resistance of R1 and R2 is high, means no airflow from the
duct, and if the resistance of R1 is high and resistance of R2 is low,
means there is airflow from the duct and the main fan is on. Additional
algorithms can be used to avoid the interference by the airflow of the
vent fan, such as to stop the vent fan for a short time to
differentiating airflow by main fan or vent fan.

[0048]In some embodiments, a regular resistor can be used as the heating
resistor and be attached to the temperature sensor resistor to heat it;
and the temperature sensor resistors are only used for sensing purpose
instead of providing heating as well.

[0049]A temperature sensor can be used in the booster. It can sense the
change of the temperature in the duct. When the booster is in on state,
if it senses a significant change of temperature of the air around it, it
will stop the booster. When the booster is in off state, if it senses a
significant change of temperature of the air around it, it will start the
booster. It can also be used as an additional sensor collaborating with
the wind sensor to determine the status of the AC and therefore turn on
or off the booster. For example, if both the temperature sensor and wind
sensor sense the AC is not working, the booster will be stopped.

[0050]In another example, a temperature detecting circuit can be used as
FIGS. 16a and 16b. Resistance of R6 is high enough to not allow the R5 to
have significant heating up. So, the temperature change can be measured
by Vt. Vt can also be used by the algorithms, as an additional parameter,
to determine the status of the main AC unit.

[0051]A temperature control and a damper can also be integrated with the
booster. The damper can either open or close to allow or block/reduce the
airflow from the duct. The damper can be build either in front of the fan
or behind the fan as long as they block/reduce the airflow if closed. The
damper can be either manually operated of powered. One of the reasons to
use damper in the booster system is for example, HVAC is set to cooling
state, sometimes the HVAC is on but the room having booster is already
cold enough; simply turning off the fan cannot stop the cold air coming
out from the duct. Therefore a temperature control can be added to the
booster system, which set the desired temperature. If the desired
temperature is meet (e.g. the room temperature is lower than the set
temperature in the summer or the room temperature is higher than the set
temperature in the winter, a winter/summer selection control can be
added), it will close the damper therefore block any more cold air coming
out from the duct. Another method is to not use damper but reverse the
rotation direction of the fan therefore the fan will try to blow air into
the duct to reduce the airflow coming out from the duct.

[0052]Furthermore, air purification device can be integrated with or
attached to the register or the booster. For example, it can be built
within the register; it can also be a tower type structure that covers
the vent of the booster. An air purification unit is inside the tower.
When the air coming from the booster pass though the air purification
unit the air will be purified and then comes out of the tower to go into
the room. Examples of the air purification units, including static
electricity filters, electrostatic precipitating cleaners, electret
filters, ozone generators, UV generators, and negative ion generators or
combinations thereof, which clean and sanitize the air by collecting
dust, killing airborne molds and bacteria, or otherwise reducing the
level of airborne pollutants. For example it could be a pair of plate
emitters electrically connected to a high voltage generator. As is known
in the art, ozone is generated in emitters via a high voltage applied
across spaced electrodes or conductive plates. In another example the air
purification unit includes a light source, which is surrounded by a
cylindrical shell of photo catalytic material (such as a titanium oxide
coated substrate). Contaminates in air passing through it are
catalytically oxidized with the energy supplied by light.

[0053]FIG. 17 illustrates a filter tower as the air purification device,
which is detachablely fixed to a booster (e.g. the tower and the booster
can be snapped together). The tower has an electrostatic precipitating
cleaner unit inside for air purification. The power supply can either be
from the booster or from its own power line or share the adapter with the
booster.

[0054]The invention described in above summary is further explained with
the following drawings that illustrate specific embodiments of the
invention.

BRIEF DESCRIPTIONS OF DRAWS

[0055]The invention described in above summary is further explained with
the following drawings that illustrate specific embodiments of the
invention.

[0072]FIG. 17 shows an embodiment of a booster with a air purification
system.

DETAILED DESCRIPTION

[0073]The following detailed description is provided as an aid to those
desiring to practice the invention disclosed herein, it is not, however,
to be construed as limiting to the instant invention as claimed, since
those of ordinary skill in the art will readily understand that
variations can be made in the examples, procedures, methods and devices
disclosed herein, without departing from the spirit or scope of the
instant invention.

[0074]FIG. 1 is an embodiment of multi-zone HVAC system. It shows
schematically the overall concept of the invention embodied herein. A
HVAC unit 1 (the indoor part of the HVAC) supplies conditioned air to two
rooms through duct 4. The outdoor part HVAC unit 2 connects with the
indoor HVAC unit 1 though pipe 3 (e.g. the heat exchange unit). Air
circulates in the room through duct 4 and HVAC air intake 5. A central
controller 7 is a combination of a zone controller and a central control
unit. As a zone controller, it controls register (air flow rate
regulating device) 9 and detect the conditions of the room (e.g.
temperature and/or the status of the register) and send it to the central
control unit part of itself. As a central control unit, it coordinates
with the zone controllers 8 and controls the HVAC unit through wire 6.
The conditioned air exits into the rooms through registers 9, which is
shown in greater detail in FIG. 2.

[0075]FIG. 2 shows an embodiment of a wireless adjustable register using
battery-powered damper. In FIG. 2, register 9 consists of a built-in
damper 10, a motor 11, one or more batteries 12, a wireless radio
receiver and transmitter 13 and a screen 14; it could also contain build
in fan or fans as a booster or contain both damper and booster. The
battery powers the motor to open or close the damper.

[0076]FIG. 3 shows the digital wireless network that connects the central
controller 7, the zone controllers 8, and the registers 9. Central
controller 7 controls and communicates with the HVAC unit through wire 6.
Each component in the wireless network has a unique network ID and a zone
controller is programmed to communicate only with register(s) 9 inside
this zone and the central controller 7. The whole system could also be
incorporated into a local network such as LAN, a home network, therefore
could work with additional computer systems. In some embodiments, the
central controller can also be connected with HVAC unit via a wireless
connection and control it wirelessly and the HVAC unit has a wireless
receiver.

[0077]FIG. 4 is a block diagram of one embodiment of the central
controller that also functions as a zone controller for the zone it is
located. Switch 15 sets the mode of the central controller to be either
heating, or cooling or ventilating or off. Buttons 16 on the controller
are used to program desired zone temperatures and can be used to enter
simple instructions to Microprocessor 19, which can have built-in control
logic as well. Slot 17 is a connection to Internet or a personal
computer. For example, it can be a USB slot or a wireless communication
port. The digital wireless receiver and transmitter 18 communicate with
its zone registers and other zone controllers. A temperature sensor 20
senses and reports the ambient temperature to the microprocessor 19.
Battery 23 supplies power to all components of the central controller.
LCD 21 displays information including: a) the set temperature, b) the
ambient temperature, c) sign for low battery power for zone controller,
d) sign for low battery power for the register(s), e) if manual override
is engaged in the register(s)and f) the current status of the HVAC. To
reduce power consumption on the register battery, microprocessor 19 is
responsible to check on the power level of the register battery, instead
of the register reporting its own power level. Each zone controller
reports the status in its zone to the central controller. When desired
condition (e.g. set temperature is reached) in all zones are achieved,
the heating/cooling of the HVAC unit is turned off by the central
controller. If one or more zones' setting are not reached, the central
controller will keep the heating/cooling of the HVAC unit on to produce
cooling or heating depend on the switch selection (e.g. if it is in
summer, the switch should be set at cooling so the central controller
will instruct the HVAC unit to produce cooling). A more complicated
algorithm can be used by the central controller for determining if it
should keep the HVAC unit on or off. For example, the zone can be grouped
by priority, if most high priority zone (e.g. bed room at night, living
room during day light) reached their setting, the central controller will
stop the HVAC unit although some low priority zone's need (e.g. living
room at night) are not meet.

[0078]FIG. 5 is a block diagram for an embodiment for the zone control
unit. Compared to the central controller depicted in FIG. 4, the zone
controller does not directly control the HVAC and does not set the HVAC
state (heating, cooling, ventilation, off).

[0079]FIG. 6 is a block diagram that shows an example of the components in
a damper type register. Circuit 35 processes the instructions received
from zone controller through wireless transmitter 34 and instructs motor
11 to drive mechanism 33 to adjust damper status accordingly to status
between completely open and completely close. A manual override is
built-in to override instructions from zone controller. When manual
override is engaged, instruction from zone controller is ignored.
Information sent to the zone controller wirelessly includes the damper
status, battery level and if manual override is engaged.

[0080]Table 1 tabulates an example for the algorithm a zone controller or
central controller employs to control the register status. The symbol A
represents the temperature dead band, which is the preset tolerance range
on temperature before damper/booster status is changed. The tolerance
range for different zones can be set to different values. For example, if
there is a zone that is more demanding than other zones in the sense that
it is usually the last to reach the set temperature and the first to
activate the HVAC unit, the tolerance range Δ for this zone could
be set the largest to avoid frequent turning on and off of the HVAC unit.
The central controller can also use the tolerance range of each zone to
control the on/off of the HVAC unit. For example, in summer and the set
temperature is 70° F. and the actual room temperature of zone 1 is
71° F. and its tolerance range Δ is 2° F. and all
other zones are satisfied, the HVAC will not be turned on by central
controller to produce cooling until the actual room temperature of zone 1
is 72° F.; it will not stop cooling until the actual room
temperature of zone 1 is 68° F.

TABLE-US-00001
TABLE 1
Damper status control logic for two-position damper
HVAC state\ Set > Set <
Temp. Setting actual + Δ actual - Δ Otherwise
Heating Open Close No Action
Cooling Close Open No Action
Ventilation Open Open Open

[0081]FIG. 7 shows the side section view of another preferred embodiment
of the register with an airflow booster. The booster can be a powered
adjustable register depicted in FIG. 2 with one or more fans 38 added.
The powered damper part may not necessarily be included. A wireless
signal transceiver 41 communicates with the zone controller and sends
control signal to motor 39, which controls fan 38 through certain
mechanism. Fan 39 is mounted on the walls of the booster through thin
metal rods 40. Screen 37 protects the fan and diffuse airflow. Power is
brought to the booster through electrical wire 42. Since the booster fans
themselves can serve as dampers when not operating or reverse the
rotating direction to blow air back to the duct, a blade damper may or
may not be needed.

[0082]Some HVAC unit operates most efficiently in certain airflow/air
pressure range. Too little airflow may cause overheating or icing. There
are many means to prevent this from happening, some of which are listed
below: [0083]1. always keep certain percentage, e.g. 20-30%, of
registers open. Usually, there are enough registers in closets and
bathrooms to meet this needs and these registers may not need to be the
powered registers; [0084]2. use booster registers in selected locations
to boost airflow. In general, the boosters can be used in zones where the
temperature conditions are more difficult to satisfy; [0085]3. register
dampers can be designed such that a certain percentage of airflow is
allowed even in a close position. [0086]4. the HVAC is not allowed to
remain on for prolonged period if less than a certain percentage of
register is open. This may result in the set temperature in certain zone
not being satisfied in one heating or cooling cycle. If the set
temperature cannot be satisfied in multiple cycles, a register booster is
recommended. [0087]5. temperature sensors can be installed near the
air-handler to detect icing or overheating. The heating/cooling will be
shut down if the temperature rise above or drop below a set level or open
more dumpers or start more boosters to increase the airflow passing the
heating/cooling unit. Pressure sensor can also be installed, if the air
pressure in the HVAC system is too high, the control unit will open more
dumpers or start more boosters to release the pressure or shut off the
HVAC system. Air flow bypass can also be installed as previously
described. [0088]6. width of the dead band for a zone can be set manually
or automatic according to the speed of the temperature fluctuation in
that zone. In general, the faster the temperature fluctuates, the wider
the dead band. [0089]7. The heating/cooling capacity is decreased to
compensate the overcooling/heating; or the power of the central will
increase therefore maintain enough airflow in the duct.

[0090]In practice, a combination of the above measures can be used. For
example, a simple means would be to keep 20% of registers always open and
use boosters in 20% of the remaining registers. Sometimes for some reason
a certain room's setting is difficult to reach (e.g. the temperature
setting for certain room is too low when cooling or too high when
heating), this room will keep the HVAC unit active for a period of time
even after all other room's needs are satisfied. A warning message can be
displayed on the zone controller and/or the central controller to remind
the user to adjust the setting in that particular room. In some
embodiments, these rules/algorithms are stored and used by the central
controller.

[0091]Wireless communication system is needed to transmit information
between the central (main) control unit, sub (zone) control units and
airflow rate regulating devices (vent units such as registers). A digital
wireless communication system is designed to have very low manufacturing
cost, reliable communication at relatively low data rate. A design
example is illustrated as the following:

[0092]FIG. 8 depicts an embodiment of the 3-layer structure of the
intelligent digital wireless communication network. The central unit
(central controller) is on the top, the sub units (zone controller) are
in the middle and the vent units (airflow rate regulating device) are on
the bottom. The central unit does not control and communicate with the
vent unit directly. The operation of the vent unit is directly controlled
by the zone controller. However in another embodiment the central
controller can also communicate with and control the vent unit to
implement certain operations and algorithm. The vent unit may also send
signal back to the zone controller (e.g. reporting its status) and/or
central controller.

[0093]Yet in another embodiment, the central controller directly controls
the vent units and the zone controller only report the zone status to the
central controller. The zone controller does not control and send command
to the vent unit therefore the corresponding part in zone controller will
not be necessary. However because the temperature setting is still
performed in zone controller, it is still called zone controller.

[0094]Yet in the third embodiment, the central controller directly
controls the airflow rate regulating device and the zone controller is
integrated with the airflow rate regulating device.

[0095]FIG. 9 is an embodiment of the structure of a control unit (central
or zone control unit) of the wireless communication system. A transceiver
is sending or receiving RF (radio frequency) signal or other wireless
signal such as infrared signal. The microprocessor is to act as encoder
or decoder during signal transmitting or receiving mode. A unique
ID/address is assigned to each central control unit during manufacturing,
and the IDs of zone control units will be preset or set during
installation to correspond to the ID of the central control unit.

[0096]FIG. 10 is an embodiment of the circuit structure of a vent unit
(airflow rate regulating device). In the simplest case, it only contains
a receiver in the RF part. If sending data to other control unit is
desired, a transceiver will be used instead of the receiver.

[0097]FIG. 11 is an embodiment of the command/data transmitting process
flow chart. During transmitting mode, the microprocessor encodes signal
with the command/data and the network ID of the unit it intends to send
signal to and enable the RF transmitter to transmit radio signal.

[0098]FIG. 12 is an embodiment of command/data receiving process flow
chart. During receiving mode, the microprocessor decodes signal received
by the receiver, processes to accept or reject according the network ID
and extracts command/data.

[0099]In some embodiment, a simplified version can be used in which the
zone controller is integrated with the register or connected with
register with wire therefore eliminate the use of corresponding parts for
wireless communication between the zone controller and the register.

[0100]Since only the zone controller need to have the RF module, the cost
can therefore be reduced. In fact it is similar to a register having a
thermostat that can wirelessly communicate with the central controller.
If more than one register is used in a zone and the zone controller is
connected with only one register with wire, the other registers in this
zone can be made to receive wireless communicate from this register/zone
controller in order to be to be turned on or off.

[0101]As previously described, normally the upper floor is much hotter
than lower floor in the summer and much cooler than other floors in the
winter if only one single zone HVAC is used; and most single zone HVAC
only use one central fan to deliver the air to each room. A simplified
method to overcome this problem is to install a second fan that can
enhance the floor rate in the main duct sending air to the upper floor
therefore providing more conditioned air to the upper floor. This second
fan is installed in the duct connecting to the upper floor only, not in
the duct also sending air to the lower floor. In some embodiments, the
on/off or speed of this fan can be controlled by a remote controller in
the upper floor. The remote controller can control the fan with the
user's manual input or with certain logic stored in the remote
controller. For example, if the remote controller sense the
heating/cooling unit of the HVAC is on and the preset temperature in the
zone in the upper floor is not met, it will turn on the second fan or
speed up the second fan. If the preset condition is met, it will turn off
the second fan. In other embodiments, the second fan can be automatically
turned on or off with the on/off of the HVAC system using the same
methods described previously for the register booster. In some cases,
certain rooms not necessarily in the upper floor also have low efficiency
cooling/heating or high cooling/heating demand. These rooms can be
treated similarly to the upper floor rooms described above by install a
similar fan in the duct connecting to these rooms only and the similar
control mechanism accordingly.

Patent applications by Shazhou Zou, Columbia, MD US

Patent applications by Tianxin Wang, Boyds, MD US

Patent applications in class Zone control for heating and cooling medium

Patent applications in all subclasses Zone control for heating and cooling medium